Brake drum



Dec. 231 1930. w SCHWEMLEIN "1,786,132

BRAKE DRUM Filed April 5. 1928 W CHWEM LEI/Y ya. l SHN;

l be driven Patented Dec. 23, 1930 UNITED STATES PATENT i OFFICE SCHWmEIN, v Oil YAIBXERSBUBG, 'WEST VIRGINIA, ASSIGNOB '10 `.lHE PABKEBSBUBG BIG & REEL COMPANY, Ol' PARKEBSBUBG, WEST VIRGINIA, A 00B- POBATION 0l' WEST VIRGINIA BRAKE DBUIV Application iled April 5,

' ture particularly adapted for use as a brake I drum in connection with the sand reel shafts of well drilling apparatus. f

In connection wi h such an apparatus, it is the present practice to 'provide a sand y reel shaft having a spool thereon, and adapted to throuh manually controlled clutch means. The s aft is provided with a brake drum adapted to be engaged by a suitable brake band. The spool mounted upon the sand reel shaft is engaged by a cable passing over a suitable sheavel and connected to the apparatus employed in connection with the drllling operation, such as the baler. The clutch is engageable for rotating the sand reel shaft to zo elevateV the baler, while lthe brake is operable to retard the lowering of the baler into the well.

The brake drum, in lan apparatus of this. character, is subjected to considerable' friction, and in operation, the engaging surface of the drum becomes heated tov temperatures as high as 700 F. The central portions of the drums remain relatively cool, and accord-Y ingly severe internal stresses are set up in 3 the metal of the drum.

An object of the present invention is to provide a drum structure ofthe character referred to wherein means is provided for per mitting the free expansion of the peripheral portions of the drumy without affecting the inner portions thereof.

A. further object is to provide a drum of the character referred to which comprises separate inner and outer portions connected in driving relationship whereby they' rotate as a unit, the outer portion referred t0 being adapted to partake of vexpansion and contraction independently :of the inner portion.

A further object is to provide novel connecting means between the inner and outer portions of the brake drum to permitdiffer ential expansion and contraction to take place between the two portions of the drum.

A further object is to provide n ovel means associated with the peripheral portion of the om a suitable source of power 1928. Serial No. 887,658.

drum for agitating air in the vicinity thereof to assist in radiating heat from such peripheral portion.

A further object is to providea device of s the character just referred to wherein the agitating means constitutesin itself means for assisting in the radiation of heat from the peripheral portion of the drum.

A. further object is to provide a device of the character referred to whereinthe air agitating means performs` the further function of providing reinforcing means for the pe'- ripheral portion of the drum.

Other objects and advantages of the inl vention will become apparent during the course of the following description.

In the drawings I have shown one embodiment of the invention. In this showing,

Figure l is a side elevation, and, Figure 2 is a section taken substantially on line 2 2 of Figure 1.

Referring to the drawings, the numerals 10 and l1 indicate respectively inner and outer sections forming in effect a single brake drum, as will be apparent. These sections include flange portions 12 and 13 respectively, arranged in radial alinement,4 as shown in Figure 2. The inner section further includes a hub 14 havin i opening 15 therein. The hub also is provided with the usual key slot 16 by means of which the inner section 10 ma be keyed to the shaft. The hub and flange. o the inner section are connected by preferably integral ribs 17.

The outer section 11 is provided with a cy-L lindrical peripheral portion 18 having its a circular shaft receiving outer face adapted for engagement with a wil be noted that the inner an outer pins 11" each other,

splice bars 20 as will be obvious, these elements forming rigid driving connections between the inner and outer sections.

vAs previously stated, the brake face of the rim 18 is subjected to theaction of friction when the device is in operation, and accord inglf becomes highly heated whereby it expan s. At the same time, the inner section 10 remains comparatively cool, and thus is not subjected to the same degree of expansion. When an integral brake drum is put to the use for which the present 'device is intended, the difference in the degree of expansion between the inner and outer portions of the drum sets up severe internal stresses which frequently cause the drums to break, thus resulting not only in damage to the parts but also in injury to operators. With the present construction, the outer section 11 is adapted to freely expand and contract without affecting the inner section in any way, the splice bars 20 pivoting slightly about the axes of the pin 21. Thus the ositive driving connection is maintained, and the device operates efficiently without danger of damage or any injury to persons.

TheV pivot ins of the links or splice bars are offset radially from each other to permit the free differential expansion and contraction referred to. Obviously, if these pivot pins were arranged in radial alinement, there would be a direct pulling or compressing force on the links, according to whether the outer section expanded or contracted. With the present construction, however, the expansion and contraction of the parts is unim eded.

the manufacture of the device, the ad- 'acent faces of the flanges 12 and 13 may be made of substantially the same diameter with only suicient clearance to permit the elements to be assembled. The matter of the clearance between these elements, how ever is not important and any desired clearance may be provide The fins 19 serve not only to provide effective reinforcing means between the rim 18 and its associated flange, but also act as radiating lins to assist in lowering the temperature of the outer section 11. In addition the fins also serve the function of agitating the `air adjacent the drum, thus assisting vin the radiating action. This agitation of air also is assisted by the fins 17 whichact as centrifugal fan blades to constantly feed air outwardly toward the outer section 11.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim 1. A device of the character described comprising a pair of concentric rotatable elements, one of said elements be'n provided with a face adapted to be engager? by a friction element and adapted to partake of expansion and contraction independentl of the other element, said elements being adapted to partake of limited relative rotation upon said expansion and contraction, and means for connecting said elements together to r0- tate as a unit.

2. A device of the character described comprisingv a pair of concentric inner and outer elements, said outer element having an annular rim provided with a face adapted to be engaged by a friction element, the outer of said elements being adapted to expand independently of the inner element, said'elements being adapted to partake of limited relative rotation upon said expansion and means for connecting said elements together to rotate as a unit.

3. A device of the character described comprising a ai'r of correlated rotatable elements, one o said elements bein provided with a face adapted to be engager? by a friction element and adapted to expand independently of the other element, andl pivotally mounted connecting means arranged between said elements.

4. A device of the character described comprising a air of concentric rotatable elements, one o said elements bein provided with a face adapted to be engager? by a friction element and adapted to expand independently of the other element, and a link pivotally connected at its ends to said rotatable elements.

5. A device of the character described comprising a pair of concentric rotatable elements arranged one within the other, the outerI element being provided with a rim having an annular face ada ted to be engaged by a friction element and eing adapted to ex pand independently of the other element, and a link pivotally connected 4at its ends to said rotatable elements.

6. A device of the character described comprising a pair of concentric rotatableele-A ments arranged one within the other, the outer element being provided with a rim having an annular face adapted to be engaged by a friction element and being adapted to expand independently of the other element, and a link pivotally connected at its ends to said rotatable elements, the pivot points of said liilk being radially offset with respect to each ot er.

' 7. A. device of the character described comprising a pair of concentric inner and outer elements each including a radial flange arranged in radial alinement with each other,

said outer element having an annular rim provided with a face ada ted to be enga ed y a friction element, sai outer element eing ada ted to ex and independently of the inner e ement, a ink arranged fiat against lo said flanges, and pivot pins connecting the ends of said link to the respective flanges. y

8.. A device of the character described comprising a pair of concentric inner and outer elements each including a radial flange arranged in radial alinement with eachother, said outer element having an annular rim provided with a face ada ted to be enga ed by a friction element, said outer elementeing adapted to expand independentl of the inner element, a plurality of pairs of inks arranged against opposite sides of said flanges, andpivot pins connecting the respective ends of said pairs of links to the respective flan es. 9. A device of the character descri ed comprising a pair of concentric inner and outer elements each including a radial flange arranged in radial alinement with each other, said outer element having an annular rim rovided with a face ada ted to be enga ed y a friction element, sai outer elementeing adapted to expand independently of the inner element, a plurality of pairs of links arranged against opposite sides of said ilanges,` and ivot pins connecting the respective ends u of sald pairs of links to the respective ianges, the pivot pins vof each pair of links being radially offset from each other.

In testimon whereof I affix my signature.

W LLIAM SCHWEMLEIN. 

